GHCall+extensions.swift

extension SearchableWebService {
    func search(term: String, handler: SearchResponseHandler? = nil) {
        let url = self.searchURL(withTerm: term)
        let task = URLSession.shared.dataTask(with: url) { data, _ , _ in
            if let data = data {
                let json = JSON(data: data)
                handler?(json["items"].arrayValue.map(T.init))
            } else {
                handler?(nil)
            }
        }
        task.resume()
    }
}


extension SingleObjectWebService {
    func getBy(key: String, response: SingleObjectResponse? = nil) {
        let url = getURL(withKey: key)
        let task = URLSession.shared.dataTask(with: url) { data, _ , _ in
            if let data = data {
                let json = JSON(data: data)
                response?(T.init(json: json))
            } else {
                response?(nil)
            }
        }
        task.resume()
    }
}

GHCall+protocols.swift

protocol SearchableWebService {
    typealias SearchResponseHandler = (([T]?) -> Void)
    associatedtype T: JSONMappable
    func searchURL(withTerm term: String) -> URL
    func search(term: String, handler: SearchResponseHandler?)
}

protocol SingleObjectWebService {
    associatedtype T: JSONMappable
    typealias SingleObjectResponse = (T?) -> Void
    func getURL(withKey key: String) -> URL
    func getBy(key: String, response: SingleObjectResponse?)
}

GHCall.swift

class GHRepositoryWebService: SearchableWebService {
    typealias T = GHRepository
    func searchURL(withTerm term: String) -> URL {
        return URL(string:"https://api.github.com/search/repositories?q=\(term)")!
    }
}

class GHOrganizationWebService: SingleObjectWebService {
    typealias T = GHOrganization

    func getURL(withKey key: String) -> URL {
        return URL(string: "https://api.github.com/orgs/\(key)")!
    }
}

class GHUserWebService: SearchableWebService, SingleObjectWebService {
    typealias T  = GHUser

    func searchURL(withTerm term: String) -> URL {
        return URL(string: "https://api.github.com/search/users?q=\(term)")!
    }

    func getURL(withKey key: String) -> URL {
        return URL(string: "https://api.github.com/users/\(key)")!
    }
}

GHModels.swift

protocol JSONMappable {
    init(json: JSON)
}

struct GHUser: JSONMappable {
    var login: String
    var id: String

    init(json: JSON) {
        self.login = json["login"].stringValue
        self.id = json["id"].stringValue
    }
}

struct GHRepository: JSONMappable {
    var id: String
    var name: String
    
    init(json: JSON) {
        self.name = json["name"].stringValue
        self.id = json["id"].stringValue
    }
}

struct GHOrganization: JSONMappable {
    var id: String
    var login: String
    
    init(json: JSON) {
        self.id = json["id"].stringValue
        self.login = json["login"].stringValue
    }
}